2. Lung ultrasound and LUSS
In COVID-19 group, there were totally 132 regions reviewed and 83 regions (62.8%) detected abnormalities. Each patient showed abnormalities in bilateral lungs and multiple regions, with maximal 10 regions, average 7.5 regions involved. The majority of detectable ultrasonic signs were increased B-lines (83 regions, 62.8%), from sparse (73 regions, 55.3%) B-lines to confluent B-lines (10 regions, 7.6%); abnormal scored 1, 10 regions (8%) scored 2 and no regions scored 0. Lung score was obviously higher in COVID-19 group than that in control group (Fig. 3). The lesions were primarily located in bilateral lower A-lines (83 regions, 62.8%), from decreased A-lines (52 regions, 39.3%) to disappear of A-line (31 regions, 23.4%); blurring, irregularities, interruption of pleural line (29 regions, 21.9%), subpleural consolidation (5 regions, 3.8%), and no pleural effusion (Fig. 2). There were 49 regions (37%) were normal, 73 regions (55%) lobes and right middle lobe (region L4, L5, L6, R3, R4, R5, R6) (Table 3).